It could be that the button is sticking and causing problems. If you are not comfortable opening the ESC to clean it thoroughly then I might suggest a can of air or an air compressor to blow around the button and make sure it is very clean and operating properly. If this is not the problem then you certainly should contact Traxxas and I bet they would be more than willing to help you. I am not even a big fan of Traxxas but I do know their customer service is next to none.